Common Name: Agarwood, Aloeswood, Oud,
Scientific Name: Aquilaria crassna
Categories: Threatened Species, Cosmetic/Medicinal;
Aquilaria crassna is a tree species that has been of great ethnobotanical importance to people throughout the Greater Mekong region and beyond. Its heartwood and resin are highly valued commodities that have been transported along long-established trade routes for thousands of years. However, this species has now become Critically Endangered, owing to over-exploitation. Currently the majority of Agarwood comes from wild populations and there is now a very real danger this species may become extinct if wild harvesting continues at the current rate. To conserve this species, it is vital that this plant becomes more widely grown in cultivation, to reduce the pressure on the few wild populations that remain.
Why is this species important?
The timber of this species is known as the ‘Wood of the Gods’ and has been known and highly appreciated for thousands of years. There is a strong connection that exists between the use of the wood, religion and curative properties.
Where is it found?
This species has a fairly wide distribution and is found is Vietnam, Cambodia, Laos and Thailand. Aquilaria crassna is a light-demanding species, which grows scattered through natural forest on rocky, shallow, ferralitic soils, often growing alongside streams. It grows within an altitudinal range of 300-900m.
How do people use it?
The wood from Aquilaria crassna contains aromatic resin, known as ‘gaharu’. This is produced by the tree in response to injury if the production of callus tissue is inhibited. It acts as a chemical barrier to attack by insects and fungi. However, under natural conditions gaharu is not produced by trees at all. This resin is often used in temples as perfume wood. The wood can also be distilled to yield a valuable essential oil, which is widely used in Chinese and Southern Asian medicine and also in the Middle East for making perfumes and cosmetics.
Why is it threatened?
Economic exploitation of this tree for both its heartwood and oil has significantly reduced the natural range of the species and has placed it under threat. Unregulated collection of both seeds and saplings from the wild occurs widely, and good income can be earnt from selling these plants. This has also reduced reproductive capacity of the species, and it now only grows in scattered stands with low numbers of individuals.
What conservation action is needed?
To conserve this species, the Vietnam Tree Seed Project has established a demonstration seed orchard in cooperation with the Central Forest Seed Company. The objective of this project is to promote the use of this species in non-timber plantations to enhance ex-situ conservation. This will help to reduce the pressure on harvesting from wild populations. It is essential that the seed orchards are used as a tool to raise awareness of the importance of conserving this species. They will also help to maintain genetic diversity among the species population. Further advantages of this project are that its methodology can eventually be implemented elsewhere and cultivation of the plant leads to valuable extra income for local people.
Many thanks to BGCI for writing this profile.
Jensen, Anders and Meilby, Henrik (2008) ‘Does commercialisation of a non-timber forest produce reduce ecological impact? A case study of the Critically Endangered Aquilaria crassna in Lao PDR’, Oryx (Volume 42, Issue 2): pp. 214 -221;
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